Forum Discussion

Lucaraheller's avatar
Lucaraheller
MCT
Mar 12, 2026

Hi JRobbins1280​ 

What you are trying to achieve makes sense from a control perspective, but today Defender for Cloud Apps sanction/unsanction governance is not natively enforced through Azure Firewall or VPN Gateway in the same way it can be enforced through Microsoft Defender for Endpoint integration.

The important architectural point is that Defender for Cloud Apps does not act as a network firewall itself. Its unsanctioned app control depends on an enforcement point. Today, the most mature native enforcement point for blocking unsanctioned cloud apps is Defender for Endpoint, where domain and URL indicators can be pushed down to managed endpoints.

That is why your RRAS + Defender for Endpoint approach works conceptually, but it is really a workaround. It introduces complexity and does not give you true application-aware enforcement at the network edge in Azure.

A few key considerations:

  • Azure Firewall can enforce FQDN / URL / TLS inspection / application rules, but it does not currently consume Defender for Cloud Apps sanction/unsanction tags as a native policy source.
  • VPN Gateway is primarily a connectivity service and does not provide the type of cloud app governance enforcement that Defender for Cloud Apps needs.
  • Defender for Cloud Apps is strongest today for:
    • discovery and classification of cloud app usage
    • sanction / unsanction governance
    • session controls via Conditional Access App Control
    • endpoint-based block integration through Defender for Endpoint

So if the goal is to secure access to approved OpenAI endpoints only, the practical patterns today are usually:

  1. Endpoint-based enforcement with Defender for Endpoint
    Best when traffic originates from managed Windows endpoints and you want direct native integration with unsanctioned app blocking.
  2. Network egress control with Azure Firewall
    Best when you want to restrict outbound access from Azure workloads to specific approved FQDNs or destinations, but this must be maintained as firewall policy logic rather than inherited automatically from Defender for Cloud Apps sanctioning.
  3. Identity/session control with Conditional Access and Defender for Cloud Apps
    Best when the concern is user access governance, session visibility, and SaaS control rather than raw network egress filtering.

For an Azure OpenAI security design, many organizations end up using a layered model:

  • Private endpoints / private networking where possible
  • Azure Firewall or other egress filtering for approved destinations
  • Defender for Cloud Apps for discovery, visibility, and governance
  • Defender for Endpoint for endpoint-based unsanctioned app enforcement
  • Conditional Access for user and session restrictions

So, to your direct question: today there is no native feature that makes Azure Firewall or VPN Gateway act as a Defender for Cloud Apps sanction/unsanction enforcement engine. Your observation is correct that the current enforcement model is much cleaner on endpoints than at the Azure network boundary.

As for future plans, Microsoft has not publicly exposed a native Azure Firewall/VPN Gateway integration for Defender for Cloud Apps sanction enforcement that I am aware of, so for now this would be more of a product feedback / roadmap request than a supported design pattern.

A good practical recommendation would be:

  • use Azure Firewall for deterministic egress restriction to approved OpenAI-related endpoints
  • use Defender for Cloud Apps for discovery and sanction governance
  • use Defender for Endpoint where endpoint-based blocking is needed
  • avoid building a custom RRAS enforcement layer unless there is no other option, because it adds operational overhead without giving you first-class integration